roughly how much does it cost in electricity to boil a litre of water in the uk?

No more than 2p or 3p

Cost of electricity varies greatly but let us assume that a Kilowatthour costs 10p.

1 kilowatthour of energy = 1000joules for 3600 seconds = 3.6megajoules.

to heat 1 litre of water from 0 C to 100 C = 100,000J

= 0.028 KWH (approx) which costs about 0.28p

Sabrewulf: Press Forward (two seconds) Back, R

u-u-u-l-l-l-t-t-t-r-r-r-a-a-a ultra combo.

So answer is about 2.6p

about a five quid if my last electricity bill is anything to go by

About 4p

2.5

i think it is approx 12.5p per kilowatt per hour

no offencwe but you seem so scroooooooogy....sitting there counting your pennies,